Dickson Industrial THDx User manual

Rev. 06/03
DICKSON
THDx
Temperature, Humidity & Dew Point Chart Recorder
Contents:
Product Specications & Features
Operating Instructions & Display Symbols
Charts & Accessories, Calibration
Instrument Anatomy
Getting Started / Installation
Keypad Operation
Dip Switch Setup & Warranty
Troubleshooting, Factory Service & Returns
Order Form
Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON
DICKSON
930 South Westwood Avenue
Addison, Illinois 60101
Phone: [phone] • E-mail: [e-mail]

Rev. 06/03
Rev. 06/03
Product Specications
Temperature Ranges: User Selectable: -20 to +120˚F (-20 to +50˚C),
+40 to +110˚F (+5 to +40˚C)
Temperature Accuracy: ±1.8˚F (±1.0˚C)
Temperature Sensor: Thermistor
Humidity Range: 0 to 95% (non-condensing)
Humidity Accuracy: ±2% from 0 and 60%, ±3% from 60 to 95%
Humidity Sensor: Monolithic IC humidity sensor
Dew Point Range: -22 to +122˚F (-30 to +50˚C)
Dew Point Accuracy: 95% to 30% RH ±2˚C, ±3.6˚F
30% to 10% RH ±4˚C, ±7.2˚F
10% to 5% RH ±8˚C, ±14.4˚F
5% to 0% RH ±49˚C, ±88.2˚F
Ambient Operating Conditions: 32 to +122˚F (0 to 50˚C), 0 to 95% RH (non-condensing)
Display Resolution: LCD, 1˚F (1˚C), 1% RH
Chart Size: 8” (20.3 cm) DIA
Recording Time: User selectable: 24 hour, 7 day or 31 day
Average Response Time: 2.5 min. for 63% of full scale
NOTE: Response time is slower when using battery
Calibration: User calibration of all variables
Product Features
• Remote sensing capability with optional extension cords (10’, 50’ and 100’ available–see Accessories)
• Alarms: Audio/Visual with High/Low setting capabilities
• Microprocessor control and electronic sensing
• C/F and RH/Dew Point switchable
• Large 8” diameter circular chart
• Min/Max feature allows display of minimum and maximum readings
• User calibration
• Locking control keypad and door
• Large digital display shows two variables at once
• User selectable recording times and temperature ranges
Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON

Rev. 06/03
Rev. 06/03
Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON
Operating Information
Display Symbols
Pens
The blue pen has a longer pen arm and records
humidity or dew point (depending on your dip switch
selection). The red pan has a shorter arm and re-
cords temperature. The pens are offset to allow the
red pen to glide under the blue pen. The blue pen
indicates the correct time and the red pen precedes
it by 3/16 of an inch.
The pens move in increments across the chart
as sensor readings change. The display provides
smoother and faster readings than the pens. At any
given time there may be a slight discrepancy in the
position of the pen and the reading on the display
due to hysteresis.
For visual spot checks the display is more ac-
curate than the pen position but both are within the
stated specications of the unit.
Pen Adjust
Pen adjustment may be needed if the pens and
display do not match exactly.
1. Make sure the pen lifting bar is lowered and
press the “Pen Home” key.
2. Turn the chart hub clockwise, rotating the chart
3. With a small screwdriver loosen the pen adjust
screw on the pen arms and adjust the pen tips
to the outer most circle on the chart.
4. Retighten the screws. After pressing “Pen
Home” again the pens should now read
correctly with the display.
Probe
The THDx probe sits in the cradle in the back of the
unit. The THDx probe comes with the standard 8”
cord. An extension cord can be ordered to allow for
remote sensing capabilities.
Cord Installation
If you have ordered an extension cord for remote
sensing capabilities follow the instructions for cord
installation listed below.
1. Turn the unit upside down or on its side so that
you can see where the probe connects to the
back of THDx.
2. Twist and pull the black rubber strain relief,
beginning on the back of the recorder body
(see “Instrument Anatomy”).
3. Slide the strain relief on the cord
4. Inside you will see a standard connector which
looks like a phone jack. Using a small screw-
driver, press retention tab and the connector
will pop out easily.
5. Remove wand from cradle by sliding upward.
Repeat steps 1 through 3 for the portion of the
cord that connects to the wand.
6. Return the wand to the cradle mounted
position by sliding the wand down into the
cradle until it ts into the grips. The probe can
also be replaced by positioning it in back of the
cradle area pressing it into the cradle until it
snaps in place.
Power Supply
We recommend using AC power with four “D”
batteries installed as a back-up power source. This
ensures that your recording will not be interrupted
when there is a power failure. When the instrument
is using battery power, the unit will update very
slowly to extend battery life. The 120V AC adapter
plugs into the back of the recorder beneath the
probe cradle.
Lo Batt: Low battery indicator
UC: the unit is in “User Calibration” mode. This
is displayed in the upper right hand corner of the
display.
Reading Update Indicator: These rectangles will
flash along the bottom of the display as long as the
recorder is taking readings. If you are using batteries
as the power source the update indicator rectangles
will still flash but the rate will be very slow in some
modes and “B” will light on display. The rectangle
furthest to the right is lit continuously when the unit
is using battery power.
MIN: This symbol is displayed when you are setting
a maximum alarm or when you have pressed the
“MIN/MAX” key and the maximum value is being
displayed.
MAX: This symbol is displayed when you are setting
a minimum alarm or when you have pressed the
“MIN/MAX” key and the maximum value it being
displayed.



E B
Alarm is on.
Figure 4

Rev. 06/03
Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON
Charts (for current pricing go to www.dicksonweb.com or call 1-800-323-2448)
Range 24 Hour Chart 7 Day Chart 31 Day Chart
-20 to +120°F C415 C417 C480
+40 to +110°F C476 C477 C481
-20 to +50°C C472 C473 C482
+5 to +40°C C478 C479 C483
Accessories (for current pricing go to www.dicksonweb.com or call 1-800-323-2448)
Description Order #
NIST Traceable Calibration 3-pt. (new unit) N300
A2LA Accredited Calibration 3-pt. (new unit) N400
RH Calibration Kit (33% and 75%) A834
Pens (3 red/3 blue) P246
10’ Probe Extension Cable A860
50’ Probe Extension Cable A865
100’ Probe Extension Cable A866
Carrying Case A709
Probe Dust Filter (see note)* A867
*to protect probe & increase life - please use dust lter in dusty environments or where RH exceeds 70%. Probe dust lter will slow down
response time.
Calibration
Your instrument was carefully tested and calibrated
before being shipped from the factory. For greatest
accuracy, we recommend factory re-calibration every
6-12 months. Call customer service at (630) 543-
3747. If you wish to do calibration yourself, follow
these procedures. Factory supplied calibration salt
capsules or electronic instruments recently calibrated
at a certied lab are recommended. Sling psychrom-
eters and instruments using mechanical sensing ele-
ments (human hair, wood elements, bimetals, etc.)
should not be used. NOTE: The unit does not have to
be recalibrated if you used a longer probe cord.
Calibrate Humidity/Dew Point (using a
controlled chamber)
1. Turn the unit on and use dip switch #5 to select
humidity or dew point (RH=#5 off, Dew
Point=#5 on). Use dip switch #3 to select °F or
°C (°F=#3 off, °C=#3 on).
2. To activate the calibration mode, turn the unit
off. Now press the “On/Off” key and the up
arrow key at the same time. The “UC” symbol
will appear in the display to indicate you are in
“User Calibration” mode.
3. Place the probe of the unit along with your
precision relative humidity/dew point instrument
(RH/Dew Point standards) into a controlled
environment chamber and allow 15 minutes for
the unit to stabilize. For best results, calibrate
the unit at levels typically monitored during
normal operation.
4. Match the THDx reading with your precision
RH/Dew Point instrument. To raise the RH/Dew
Point reading, press the up arrow key. To lower
the RH/Dew Point press the down arrow key.
5. When calibrating is complete, simply press the
“On/Off” key to save calibration setting.
Calibrating in an open room, without the use of a
salt capsule or a chamber, is not recommended as
humidity can vary greatly within a very small area.
Calibrate Temperature
1. Press the “On/Off” key and the up arrow
simultaneously to enter the “User Calibration”
mode. Use dip switch #3 to select °F or °C.
(°F=#3 off, °C=#3 on). The display should read
“UC” in the upper right hand corner of the
display.
2. Place the THDx probe, along with your precision
temperature instrument (your temperature
standard) into a controlled environmental
chamber allowing both instruments to completely
stabilize for approximately 1 hour.
3. Match the THDx reading with your precision
temperature instrument.
4. To raise temperature reading, press the “Alarm
Set” key. To lower the temperature reading press
the “Alarm On/Off” key. Each key press adjusts
the reading by 1°F.
5. When calibration is complete, simply press the
“On/Off” key to save calibrated changes.
Calibration is stored in memory even after you turn
the unit off. User calibration information will not be
lost of AC power fails.

Rev. 06/03
Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON
Instrument Anatomy
Figure 1
Figure 2
Alarm Sound
Source
AC Adapter
Jack
Strain Relief
Probe
Pen Lifting Bar
Chart Hub
Timing ClipTemperature
Pen
Humidity/
Dew Point Pen
Pen Cap
Holders
Chart
Guide Clip

Rev. 06/03
Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON
Getting Started
Your THDx recorder has been preset to operate using
the post popular settings.
Recording Time: 7 day
°F/C: °F
Temperature Range: -20 to +120°F
Variables Recorded: °F and %RH
Pens and a chart have already been installed for your
convenience. All you need to do to start using your
THDx recorder with the settings listed above is fol-
low these quick start instructions:
1. Plug in the AC adapter
2. Set the appropriate time by inserting a coin
Chart Installation
1. Press the “Pen Home” key to make pens move to
the outside of the chart.
2. Press the pen lifting bar to raise the pens.
Remove the recorded chart if present.
3. Place the new appropriate chart on the chart hub,
being certain that the edge of the chart slides
under the chart guide clips located at the outside
of the chart. NOTE: The chart should lay flat on
the dial face.
into the groove in the chart hub and turning
clockwise until the correct hour and day on
the chart is referenced to the timing clip (see
“Instrument Anatomy” if you need assistance
locating instrument parts).
3. Remove the protective pen caps
4. Press the “On/Off” key and the pens will move to
the current reading.
After you get started using the “Quick Start
Instructions,” we recommend that you also read the
rest of the manual to ensure that you get the most
our of your instrument.
Requires 4 “D” size batteries for battery back-up.
4. Set time by inserting a coin into the groove in the
chart hub and turning clockwise until the correct
hour (and day if applicable) on the chart is
referenced to the timing clip.
5. Lower the pen lifting bar so that the pen tips rest
firmly on the paper.
6. Press the pen home key to return the pens to
position. At the end of tone recording time cycle,
simply repeat steps 1-5, replacing the used chart
with a new one.
Pen Installation
1. Press the “Pen Home” key to return pen to the home position.
2. Use the “Pen Arm” lifter to raise the pens.
3. Simply slide used pen cartridge off and slide new one on. Lower pen arm lifter.
4. Press the “Pen Home” key to return pen to chart position.

Rev. 06/03
Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON
Keypad Operation
On/Off
When you press the “ON/OFF” key the pens will
move to the correct reading.
Alarm Set
The alarm set keys are labeled with arrows that
point up and down. You can set a minimum and
maximum alarm for both of the two variables you
are recording.
1. To set the alarms press the “ALARM SET” key.
The MIN symbol will be displayed and the
temperature will flash. (Note: The alarm set
function always starts with temperature. If
you do not want an alarm to sound for
temperature readings set the alarms for points
that are outside of the range.)
2. Use the up arrow button to increase the
minimum temperature alarm setting and the
down arrow to decrease the minimum
temperature alarm setting.
3. Press “ALARM SET” key a second time. The
MAX symbol will appear and the temperature
will flash indicating that you can now set the
maximum temperature alarm. Use the same
procedure as in step 2 above for setting the
temperature maximum alarm setting.
4. Press the “ALARM SET” key a third time and
the MIN symbol will appear and humidity
(or dew point dip switch #5 is on) will flash.
Use the same process as in steps 2 and 3
above to set humidity and dew point alarm.
5. When you have set alarms for both variables
press “ALARM SET” a final time to lock in
settings.
The defaults for alarm settings are:
Temperature: +40°F min to +110°F max
Humidity: 20% min, 80% max
NOTE: Alarm settings will return to the default when
AC power fails and there are no batteries installed
for back-up power.
Alarm ON/OFF
This button turns the alarms on and off. When
alarms are “ON” the alarm symbol appears on the
display. When alarm sounds it will sound audibly for
approximately 1 minute and then it will stop. For a
visual, the variable that has moved outside of the
minimum or maximum points that you set will flash
(i.e. if you set a maximum alarm for +80°F and tem-
perature reaches +80°F the temperature portion of
the display will flash).
MIN/MAX
1. Press the “MIN/MAX” key once and the
minimum values, during the recording time,
will be displayed for 7 seconds.
2. Press the “MIN/MAX” key again and the
maximum values, during the recording time,
will be displayed for 7 seconds.
3. Press the “MIN/MAX” key a third time during
this period and the display will show current
readings. The unit will always return to current
readings mode after 7 seconds.
NOTE: Turning the unit off resets the minimum and
maximum values.
Pen Home
Press the “PEN HOME” key while the unit is operat-
ing and the pens move to the outside of the chart.
Press the “PEN HOME” key again and the pens will
return to current reading points on the chart.
Display Change
Press the “DISPLAY CHANGE” key and the display
will temporarily show the reading opposite of what
is being recorded (i.e. if dip switch #5 is off and
you are recording the RH, pressing the “DISPLAY
CHANGE” key will temporarily change the display to
show the dew point reading).
NOTE: If the unit does not respond to keypad, check
to see that dip switch #8 is off.
ON/OFF
MIN/MAX
DISPLAY
CHANGE
PEN
HOME
ALARM
SET
ALARM
ON/OFF
Figure 3

Rev. 06/03
Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON
Warranty
Dickson warrants that the products it sells will be free from defects in material and workmanship under
normal use and service for a period of twelve months after delivery. In the event of a claim under this
warranty, the product or part must be returned to the factory for repair or replacement (shipping pre-paid)
with a Return Authorization Number (see Return Information above). It will be repaired at Dickson’s option
without charge. This warranty DOES NOT cover routine calibration, pen, chart and battery replacement. The
foregoing warranty and remedy are exclusive and in lieu of all other warranties either expressed or implied.
Dickson shall not be liable for consequential or incidental damages resulting from failure or malfunction of
its products. Dickson makes no warranty for products not manufactured by it or for any products modied by
buyer, or subject to misuse or neglect.
Dip Switch Setup
To set-up the THDx for your specic application, you
might need to change some of the Dip Switches.
Every time you change a dip switch setting, you must
push the up arrow key on the keypad to activate the
new dip switch settings.
Recording Time
The THDx has four different recording time options:
1 day, 7 day, 14 day and 31 day. Dip Switch #1 and
#2 control the recording time.
7 day #1 off
#2 off
1 day #1 off
#2 on
14 day #1 on
#2 off
31 day #1 on
#2 on
NOTE: Remember to install correct chart to match
corresponding switch setting.
°F/C
You can record in °F or °C with the THDx by using
dip switch #3.
°F #3 off
°C #3 on
Temperature Range
The THDx will record in two temperature ranges.
Dip switch #4 allows you to select the temperature
range.
Wide Range
-20 to +120°F (-20 to +50°C) #4 off
Narrow Range
+40 to +110°F (+5 to +40°C) #4 on
RH/Dew Point
Dip switch #5 allows you to select whether RH or
dew point is recorded by the blue pen. (The red pen
always records temperature.)
RH #5 off
Dew Point #5 on
NOTE: When the blue pen is recording dew point,
the reading indicates the temperature at which dew
will form, so you should use the temperature scale
on the chart to read dew point.
Display
The THDx has a dual display that shows both
temperature and humidity (or temperature and dew
point if dip switch #5 is on). With dip switch #6 you
can control the position of the variables displayed.
Temperature on top #6 off
Temperature on bottom #6 on
Display On/Off
Dip switch #7 will allow you to turn the display on
and off.
Display On #7 off
Display Off #7 on
Keypad Lock
For security purposes it is possible to lock the key
pad with the use of dip switch #8. You may want
to lock the keypad to prevent unauthorized persons
from using the keypad to set alarms or change the
calibration. (For more information on use of the
keypad see “Keypad Operations” on pg. 5.)
Keypad Unlocked #8 off
Keypad Locked #8 on
1 2 3 4 5 6 7 8
Off
Figure 5

Rev. 06/03
Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON
Troubleshooting
Problem Solution
Temperature Pen & Display do not match • Check dip switch setting & proper chart
• May also be hysteresis, see page 4, “Pens”
• Need for pen adjustment, see page 4, “Pen Adjust”
Instrument is not responding to key presses • Keypad may be locked, check dip switch #8
• Slower, firmer key presses (may take multiple presses)
Instrument turns off • Check AC adapter connection (widen prongs of adapter to
fit together)
• Display may be off, check dip switch #7
Probe exposed to environments exceeding • Probe should be dried out under normal ambient conditions
95%RH for extended period –time required varies on temperature, RH and air flow
Alarm symbol is flashing in digital display • Alarm sounds audibly for 60 seconds if out of range
conditions occur, then indicator will flash until alarm key is
depressed and alarm is reset (depress MIN/MAX keys for
information)
Display shows dc and indicator on the left • Factory repair is necessary, send to Dickson for repair
part of the digital display
Display shows E (lower left of digital display) • System error or error in calibration, send to Dickson
Out of calibration or questionable accuracy • Instrument exposed to harsh environments or stressful
conditions, see “Calibration” procedure in manual
• Return to factory for re-calibration
Display won’t light up • Check dip switch #7, switch should be off
Unit won’t work at all • Check both dip switch #7 & #8. Both should be off to
allow operation
Pen trace too fine or absent • Pen may need to be replaced, moistened, or sanded
• Remove pen cap
Display shows Err • Temperature being monitored is too high, see pg. 2
Display shows Prob • Temperature being monitored is extremely cold or probe
is disconnected
Display shows cold • Temperature being monitored is too low, see pg. 2
Display shows frozen • Reset the unit by shutting it down (unplug the AC adapter
and take the batteries out) then restore power source and
turn it on
Factory Service & Returns
Contact the factory (630-543-3747) for a Return Authorization (RA) Number before returning any instrument. The
model number, serial number and a purchase order number will be requested before an RA number is issued.
• Carefully repack the instrument, label the outside of the box with the RA# and return the instrument
(freight pre-paid) to Dickson.
• All instruments that do not have the RA# clearly marked on the outside of the box will be refused. When
returning instruments for credit, please include all accessories in shipment.
• Calibration/Freight charges are non-refundable.
NOTE: Dickson shall not be liable for consequential or incidental damages resulting from failure or malfunction of
its products.
Customer Satisfaction
Dickson takes pride in providing you, the customer, with the highest quality instrumentation. We welcome the
opportunity to help you in any way possible. Whether it be a question or a new idea in documentation, the Dickson
Company would like to hear your response. Please call our Customer Service Department at 1-800-323-2448 or
[phone] (in Illinois).
Software Return Policy
IMPORTANT-Read your Software License Agreement carefully before installing software. DIckson will accept
returns for replacement of defective disks and CDs only.

Product
Specications
& Features
Operating
Information &
Display Symbols
Charts &
Accessories,
Calibration
Instrument
Anatomy
Getting
Started/
Installation
Keypad
Operation
Dip Switch
Setup &
Warranty
Troubleshooting
Factory Service
& Returns
DICKSON
Step 1 - Bill To:
Name
Company
Address
City
State Zip
Phone ( ) –
Email
Step 2 - Ship To (if different than above)
Name
Company
Address
City
State Zip
Phone ( ) –
Email
Step 3 - Ordering Information
Order # Quantity Price/Unit Total
$ /each $
$ /each $
$ /each $
$ /each $
Subtotal: $
In Illinois, add 7.5% sales tax 4 Tax: $
Freight: $
All Prices in U.S. Dollars 4 Total: $
Step 4 - Payment Method
Check: Check #
Money Order
Credit Card:
Credit Card Number: Expires: (mm/yy)
– – – /
Signature
Purchase Order: P.O.# (Net 15 days for established customers)
Customer #:
U.S.A. Freight Charges
Fax to: 1-800-676-0498 Mail to: Dickson, 930 S. Westwood Ave, Addison, IL 60101
Total Order UPS 2nd Day UPS Next UPSGround
$0-100 $15 $31 $9
$101-400 $19 $39 $14
$401-700 $26 $53 $17
$701-1,000 $35 $56 $24
$1,001-1,500 $52 $72 $36
$1,501-2,000 $69 $91 $43
$2,001-over Please call Dickson Customer Service
All shipments UPS 2nd day unless otherwise requested.